Airway epithelial cell cultures are instrumental for studying basic and applied aspects of cellular biology and physiology relevant to respiratory tract disease and its treatment. Human bronchial epithelial (HBE) cell cultures displaying mucociliary differentiation are n excellent model to better understand the function of purinergic receptors, expression of molecular regulating local levels of agonists, cell polarization, compartmentalization and molecular targeting and ciliary beating. The routine supply of large numbers of HBE cells and well-differentiated HBE cell cultures to Project investigators is a new but critical component of the current PPG. The Cell Culture Core will provide three major functions specified below.